This study is designed to assess the efficacy and safety of BMY-42215-1 (deoxyspergualin, DSG) plus intravenous pulse corticosteroids compared with placebo plus intravenous pulse corticosteroids in the treatment of patients with acute renal allograft rejection episodes. The intent of the study is to establish whether the addition of 15-deoxyspergualin- trichloride to corticosteroids will improve the outcomes of rejection therapy and reduce the need for treatment with antilymphocyte agents such as OKT3 or ATGAM.